Performance-enhanced and storage stable protease variants

- HENKEL AG & CO. KGAA

Proteases may include an amino acid sequence which has at least 70% sequence identity with the amino acid sequence given in SEQ ID NO:1 over its entire length and has, based on the numbering according to SEQ ID NO:1, (i) two or more first amino acid substitutions at positions corresponding to positions 3, 4, 99, 199, or combinations thereof; and (ii) one or more second amino acid substitutions at positions corresponding to positions 74, 136, 143, 154, 161, 163, 171, 200, 203, 209, 212, 256, or combinations thereof. Proteases of this kind demonstrate very good stability with good cleaning performance.

Skip to: Description  ·  Claims  ·  References Cited  · Patent History  ·  Patent History
Description
CROSS-REFERENCE TO RELATED APPLICATION

The present application claims priority to European Patent Application Serial No.: 18 209 175.1 according to 35 U.S.C. § 119, which was filed on Nov. 29, 2018; which is incorporated herein by reference in its entirety and for all purposes.

TECHNICAL FIELD

The invention is in the field of enzyme technology. The invention relates to proteases, the amino acid sequences of which have been altered to give them a better storage stability and/or to improve their cleaning performance, in particular with regard to the use in washing and cleaning agents, in particular with regard to liquid washing and cleaning agents, and also relates to the nucleic acids coding for said proteases and to the production thereof. The invention further relates to the uses of these proteases and to methods in which they are used, as well as to agents containing them, in particular washing and cleaning agents, in particular liquid washing and cleaning agents.

BACKGROUND

Proteases are some of the technically most important enzymes. They are the longest established enzymes for washing and cleaning agents, and are contained in virtually all modern, effective washing and cleaning agents. They bring about the decomposition of protein-containing stains on the item to be cleaned. Of these, in turn, proteases of the subtilisin type (subtilases, subtilopeptidases, EC 3.4.21.62) are particularly important, which are serine proteases due to the catalytically active amino acids. They act as non-specific endopeptidases and hydrolyze any acid amide bonds that are inside peptides or proteins. Their optimum pH is usually in the distinctly alkaline range. The article “Subtilases: Subtilisin-like Proteases” by R. Siezen, pages 75-95 in “Subtilisin enzymes,” published by R. Bott and C. Betzel, New York, 1996, gives an overview of this family, for example. Subtilases are, naturally, formed from microorganisms. In particular, the subtilisins formed and secreted by Bacillus species are the most significant group of subtilases.

Examples of the subtilisin proteases used in washing and cleaning agents are the subtilisins BPN′ and Carlsberg, the protease PB92, the subtilisins 147 and 309, the alkaline protease from Bacillus lentus, in particular from Bacillus lentus DSM 5483, the subtilisin DY and the enzymes thermitase, proteinase K and proteases TW3 and TW7, which belong to the subtilases but no longer to the subtilisins in the narrower sense, and variants of said proteases having an amino acid sequence that has been altered with respect to the starting protease. Proteases are altered, selectively or randomly, by methods known from the prior art, and are thereby optimized for use in washing and cleaning agents, for example. This includes point, deletion or insertion mutagenesis, or fusion with other proteins or protein parts. Appropriately optimized variants are therefore known for the majority of proteases known from the prior art.

International patent applications WO95/23221A1, WO92/21760A1 and WO2013/060621A1 disclose variants of the alkaline protease from Bacillus lentus DSM 5483, which are suitable for use in washing or cleaning agents. Furthermore, the international patent applications WO2011/032988A1 and WO2016/096714A1 and the European patent application EP3044302A1 disclose washing and cleaning agents which contain variants of the alkaline protease from Bacillus lentus DSM 5483. The protease variants disclosed in these documents may be altered, among other positions, at positions 3, 4, 99 and/or 199, in the counting method of the alkaline protease from Bacillus lentus DSM 5483 and, for example, having the amino acids 3T, 4I, 99E or 199I at the said positions. However, combinations of other alterations, as described below, are not disclosed in these documents.

In general, only selected proteases are suitable for use in liquid, surfactant-containing preparations in any case. Many proteases do not exhibit sufficient catalytic performance in such preparations. For the use of proteases in washing and cleaning agents, therefore, a high catalytic activity under conditions as they are during a wash cycle and a high storage stability is particularly desirable.

Consequently, protease and surfactant-containing liquid formulations from the prior art are disadvantageous in that the proteases contained, under standard washing conditions (e.g. in a temperature range of from 20° C. to 40° C.), do not have satisfactory proteolytic activity or are not sufficiently storage-stable and the formulations therefore do not exhibit optimal cleaning performance on protease-sensitive stains.

SUMMARY

Surprisingly, it has now been found that a protease of the alkaline protease type from Bacillus lentus DSM 5483 or a sufficiently similar protease (based on the sequence identity) which has, based on the numbering according to SEQ ID NO:1, (i) at least two of the amino acid substitutions 3T, 4I, 99E or 199I, at at least two of the positions corresponding to positions 3, 4, 99 or 199, and (ii) at least one amino acid substitution, in particular at least one of the amino acid substitutions 74D, 74E, 74Q, 136Q, 143L, 143W, 143Y, 154D, 154Q, 161T, 163G, 171L, 200A, 200L, 200S, 200T, 203K, 203V, 203W, 209W, 212N, 212S, 212T, 256D, 256E or 256Q, at at least one of the positions corresponding to positions 74, 136, 143, 154, 161, 163, 171, 200, 203, 209, 212 or 256, is improved in terms of its storage stability and/or washing performance and/or its stability compared with the wild-type form (SEQ ID NO:1) or a starting variant (SEQ ID NO:2 from WO2013/060621A1), and is therefore particularly suitable for use in washing or cleaning agents.

A protease may include an amino acid sequence which has at least 70% sequence identity with the amino acid sequence given in SEQ ID NO:1 over its entire length and has, based on the numbering according to SEQ ID NO:1, (i) at least two amino acid substitutions at at least two of the positions corresponding to positions 3, 4, 99 or 199, and (ii) at least one amino acid substitution at at least one of the positions corresponding to positions 74, 136, 143, 154, 161, 163, 171, 200, 203, 209, 212 or 256.

A method is disclosed for preparing a protease as defined above, comprising (i) introducing at least two amino acid substitutions at at least two of the positions corresponding to positions 3, 4, 99 or 199, based on the numbering according to SEQ ID NO:1, and (ii) introducing at least one amino acid substitution at at least one of the positions corresponding to positions 74, 136, 143, 154, 161, 163, 171, 200, 203, 209, 212 or 256, based on the numbering according to SEQ ID NO:1, into a starting molecule having an amino acid sequence which has at least 70% sequence identity with the amino acid sequence given in SEQ ID NO:1 over its entire length.

A protease within the meaning of the present patent application therefore covers both the protease as such and a protease produced by a method. All statements regarding the protease therefore relate both to the protease as such and to the proteases prepared by means of corresponding methods.

Further aspects relate to the nucleic acids coding for these proteases, to non-human host cells containing proteases or nucleic acids, and to agents comprising proteases, in particular washing and cleaning agents, to washing and cleaning methods, and to uses of the proteases in washing or cleaning agents in order to remove protein-containing stains.

These and other aspects, features and advantages will become apparent to a person skilled in the art through the study of the following detailed description and claims. Any feature from one embodiment can be used in any other embodiment. Furthermore, it will readily be understood that the examples contained herein are intended to describe and illustrate, but not to limit, the invention and that, in particular, the invention is not limited to these examples.

DETAILED DESCRIPTION

It has been discovered that amino acid substitutions at the positions described herein result in improved storage stability and/or improved cleaning performance of this altered protease in washing and cleaning agents.

Numerical ranges that are indicated in the format “from x to y” also include the stated values. If several preferred numerical ranges are indicated in this format, it is self-evident that all ranges that result from the combination of the various endpoints are also included.

“At least one,” as used herein, means one or more, i.e. 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14 or more.

“Liquid,” as used herein, includes liquids and gels as well as pasty compositions. It is preferred for the liquid compositions to be flowable and pourable at room temperature, but it is also possible that they have a yield point.

In embodiments, the alteration(s) (i) at at least two of the positions corresponding to positions 3, 4, 99 or 199, based on the numbering according to SEQ ID NO:1, and (ii) at at least one of the positions corresponding to positions 74, 136, 143, 154, 161, 163, 171, 200, 203, 209, 212 or 256, based on the numbering according to SEQ ID NO:1, result(s) in improved cleaning performance of this modified protease in washing and cleaning agents on at least one protease-sensitive stain. Proteases therefore enable improved removal of at least one, such as a plurality of protease-sensitive stains on textiles and/or hard surfaces, for example crockery.

In embodiments, the alteration(s) (i) at at least two of the positions corresponding to positions 3, 4, 99 or 199, based on the numbering according to SEQ ID NO:1, and (ii) at at least one of the positions corresponding to positions 74, 136, 143, 154, 161, 163, 171, 200, 203, 209, 212 or 256, based on the numbering according to SEQ ID NO:1, result(s) in improved storage stability of this modified protease in washing and cleaning agents.

In embodiments of the protease, the protease has (i) at least two amino acid substitutions, selected from the group consisting of 3T, 4I, 99E or 199I, at at least two of the positions corresponding to positions 3, 4, 99 or 199, and (ii) at least one amino acid substitution, selected from the group consisting of 74D, 74E, 74Q, 136Q, 143L, 143W, 143Y, 154D, 154Q, 161T, 163G, 171L, 200A, 200L, 200S, 200T, 203K, 203V, 203W, 209W, 212N, 212S, 212T, 256D, 256E and 256Q, at at least one of the positions corresponding to positions 74, 136, 143, 154, 161, 163, 171, 200, 203, 209, 212 or 256.

In embodiments, the protease has (i) at least two amino acid substitutions, selected from the group consisting of 3T, 4I, 99E or 199I, at at least two of the positions corresponding to positions 3, 4, 99 or 199, and (ii) at least one amino acid substitution, selected from the group consisting of 74D, 74E, 74Q, 136Q, 143L, 143W, 143Y, 154D, 154Q, 161T, 163G, 171L, 200A, 200L, 200S, 200T, 203K, 203V, 203W, 209W, 212N, 212S, 212T, 256D, 256E and 256Q, at at least one of the positions corresponding to positions 74, 136, 143, 154, 161, 163, 171, 200, 203, 209, 212 or 256, the combination of the at least two amino acid substitutions from group (i) and the at least one amino acid substitution from group (ii) resulting in improved cleaning performance of this altered protease in washing and cleaning agents on at least one protease-sensitive stain.

In embodiments, the protease has (i) at least two amino acid substitutions, selected from the group consisting of 3T, 4I, 99E or 199I, at at least two of the positions corresponding to positions 3, 4, 99 or 199, and (ii) at least one amino acid substitution, selected from the group consisting of 74D, 74E, 74Q, 136Q, 143L, 143W, 143Y, 154D, 154Q, 161T, 163G, 171L, 200A, 200L, 200S, 200T, 203K, 203V, 203W, 209W, 212N, 212S, 212T, 256D, 256E and 256Q, at at least one of the positions corresponding to positions 74, 136, 143, 154, 161, 163, 171, 200, 203, 209, 212 or 256, the combination of the at least two amino acid substitutions from group (i) and the at least one amino acid substitution from group (ii) resulting in improved storage stability of this altered protease in washing and cleaning agents.

In embodiments, the protease has (i) at least two amino acid substitutions, selected from the group consisting of 3T, 4I, 99E or 199I, at at least two of the positions corresponding to positions 3, 4, 99 or 199, and (ii) at least one amino acid substitution, selected from the group consisting of 74D, 74E, 74Q, 136Q, 143L, 143W, 143Y, 154D, 154Q, 161T, 163G, 171L, 200A, 200L, 200S, 200T, 203K, 203V, 203W, 209W, 212N, 212S, 212T, 256D, 256E and 256Q, at at least one of the positions corresponding to positions 74, 136, 143, 154, 161, 163, 171, 200, 203, 209, 212 or 256, the combination of the at least two amino acid substitutions from group (i) and the at least one amino acid substitution from group (ii) resulting in both improved cleaning performance and improved storage stability of this altered protease in washing and cleaning agents.

Certain embodiments of the proteases have improved storage stability. They have increased stability in washing or cleaning agents in comparison with the wild-type enzyme (SEQ ID NO: 1) and in particular also compared with the starting variant of the protease (SEQ ID NO:2 from WO2013/060621A1), in particular when stored for 3 or more days, 4 or more days, 7 or more days, 10 or more days, 12 or more days, 14 or more days, 21 or more days or 28 or more days.

Specific embodiments of the proteases may, independently of or in addition to increased storage stability, also have increased catalytic activity in washing or cleaning agents. In various embodiments, the proteases may have a proteolytic activity which, based on the wild type (SEQ ID NO: 1) and/or a starting variant of the protease which is already performance-enhanced (SEQ ID NO:2 from WO2013/060621A1), is at least 101%, 102%, 103%, 104%, 105%, 106%, 107%, 108%, 109% or 110%. Such performance-enhanced proteases allow improved washing results on proteolytically sensitive stains in various temperature ranges, in particular in a temperature range of from 20° C. to 40° C.

Furthermore, embodiments of proteases have a particular stability in washing or cleaning agents, for example against surfactants and/or bleaching agents and/or chelators and/or against temperature influences, in particular against high temperatures, for example between 50° C. and 65° C., in particular 60° C., and/or against acidic or alkaline conditions and/or against pH changes and/or against denaturing or oxidizing agents and/or against proteolytic degradation and/or against a change in the redox ratios. With embodiments, performance-enhanced and/or more temperature-stable protease variants are therefore provided. With other performance-enhanced and more temperature-stable protease variants are provided. Such advantageous embodiments of proteases therefore allow for improved washing results on protease-sensitive stains in a wide temperature range.

Cleaning performance is understood to mean the brightening performance on one or more stains, in particular on laundry or crockery. Both the washing or cleaning agent comprising the protease, or the washing or cleaning liquor formed by said agent, and the protease itself each exhibit their own cleaning performance. The cleaning performance of the enzyme therefore contributes to the cleaning performance of the agent or of the washing or cleaning liquor formed by the agent. The cleaning performance is ascertained as specified further below.

Washing liquor is understood to mean the stock solution containing the washing or cleaning agent which acts on textiles or fabric or hard surfaces and thus comes into contact with stains on textiles or fabrics or hard surfaces. Usually, the washing liquor is formed when the washing or cleaning process begins and the washing or cleaning agent is diluted with water, for example in a dishwasher, a washing machine or another suitable container.

The proteases exhibit enzymatic activity, i.e. they are capable of hydrolyzing peptides and proteins, in particular in a washing or cleaning agent. A protease is therefore an enzyme which catalyzes the hydrolysis of amide/peptide bonds in protein/peptide substrates and is thus able to cleave proteins or peptides. Furthermore, a protease is a mature protease, i.e. the catalytically active molecule without signal peptide(s) and/or propeptide(s). Unless stated otherwise, the sequences given also each refer to mature (processed) enzymes.

In various embodiments, the protease is a free enzyme. This means that the protease can act directly with all the components of an agent and, if the agent is a liquid agent, that the protease is in direct contact with the solvent of the agent (e.g. water). In other embodiments, an agent may contain proteases that form an interaction complex with other molecules or that contain a “coating.” In this case, an individual protease molecule or multiple protease molecules may be separated from the other constituents of the agent by a surrounding structure. Such a separating structure may arise from, but is not limited to, vesicles such as a micelle or a liposome. The surrounding structure may also be a virus particle, a bacterial cell or a eukaryotic cell. In various embodiments, an agent may include cells of Bacillus pumilus or Bacillus subtilis which express the proteases, or cell culture supernatants of such cells.

In various embodiments, the protease comprises an amino acid sequence that is at least 70%, 71%, 72%, 73%, 74%, 75%, 76%, 77%, 78%, 79%, 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 90.5%, 91%, 91.5%, 92%, 92.5%, 93%, 93.5%, 94%, 94.5%, 95%, 95.5%, 96%, 96.5%, 97%, 97.5%, 98%, 98.5%, 98.8%, 99% and 99.5% identical to the amino acid sequence given in SEQ ID NO:1 over its entire length and has, based on the numbering according to SEQ ID NO:1, (i) at least two amino acid substitutions at at least two of the positions corresponding to positions 3, 4, 99 or 199, the at least two amino acid substitutions may be selected from the group consisting of 3T, 4I, 99E or 199I, and (ii) at least one amino acid substitution at at least one of the positions corresponding to positions 74, 136, 143, 154, 161, 163, 171, 200, 203, 209, 212 or 256, the at least one amino acid substitution may be selected from the group consisting of 74D, 74E, 74Q, 136Q, 143L, 143W, 143Y, 154D, 154Q, 161T, 163G, 171L, 200A, 200L, 200S, 200T, 203K, 203V, 203W, 209W, 212N, 212S, 212T, 256D, 256E and 256Q.

In embodiments, the protease has an amino acid sequence that is at least 70%, 71%, 72%, 73%, 74%, 75%, 76%, 77%, 78%, 79%, 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 90.5%, 91%, 91.5%, 92%, 92.5%, 93%, 93.5%, 94%, 94.5%, 95%, 95.5%, 96%, 96.5%, 97%, 97.5%, 98%, 98.5%, 98.8%, 99% and 99.5% identical to the amino acid sequence given in SEQ ID NO:1 over its entire length and has, based on the numbering according to SEQ ID NO:1, (i) at least three amino acid substitutions at at least three of the positions corresponding to positions 3, 4, 99 or 199, the at least three amino acid substitutions may be selected from the group consisting of 3T, 4I, 99E or 199I, and (ii) at least one amino acid substitution at at least one of the positions corresponding to positions 74, 136, 143, 154, 161, 163, 171, 200, 203, 209, 212 or 256, the at least one amino acid substitution may be selected from the group consisting of 74D, 74E, 74Q, 136Q, 143L, 143W, 143Y, 154D, 154Q, 161T, 163G, 171L, 200A, 200L, 200S, 200T, 203K, 203V, 203W, 209W, 212N, 212S, 212T, 256D, 256E and 256Q.

In embodiments, the protease has an amino acid sequence that is at least 70%, 71%, 72%, 73%, 74%, 75%, 76%, 77%, 78%, 79%, 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 90.5%, 91%, 91.5%, 92%, 92.5%, 93%, 93.5%, 94%, 94.5%, 95%, 95.5%, 96%, 96.5%, 97%, 97.5%, 98%, 98.5%, 98.8%, 99% and 99.5% identical to the amino acid sequence given in SEQ ID NO:1 over its entire length and has, based on the numbering according to SEQ ID NO:1, (i) the amino acid substitutions 3T, 4I, 99E and 199I, and (ii) at least one amino acid substitution at at least one of the positions corresponding to positions 74, 136, 143, 154, 161, 163, 171, 200, 203, 209, 212 or 256, the at least one amino acid substitution may be selected from the group consisting of 74D, 74E, 74Q, 136Q, 143L, 143W, 143Y, 154D, 154Q, 161T, 163G, 171L, 200A, 200L, 200S, 200T, 203K, 203V, 203W, 209W, 212N, 212S, 212T, 256D, 256E and 256Q.

When a protease has at least one of the given amino acid substitutions, this means that it contains one (of the given) amino acid substitution(s) at the relevant position, i.e. at least the given positions are not otherwise mutated or deleted, for example by fragmenting of the protease.

The identity of nucleic acid or amino acid sequences is determined by a sequence comparison. This sequence comparison is based on the BLAST algorithm established and commonly used in the prior art (cf. for example Altschul et al. (1990): “Basic local alignment search tool,” J. Mol. Biol. 215: 403-410, and Altschul et al. (1997): “Gapped BLAST and PSI-BLAST: a new generation of protein database search programs,” Nucleic Acids Res. 25:3389-3402) and in principle occurs by associating similar sequences of nucleotides or amino acids in the nucleic acid or amino acid sequences. A tabular association of the positions concerned is referred to as alignment. Another algorithm available in the prior art is the FASTA algorithm. Sequence comparisons (alignments), in particular multiple sequence comparisons, are created using computer programs. The Clustal series (cf. for example, Chenna et al. (2003): “Multiple sequence alignment with the Clustal series of programs,” Nucleic Acid Res. 31:3497-3500), T-Coffee (cf. for example Notredame et al. (2000): “T-Coffee: A novel method for multiple sequence alignments,” J. Mol. Biol. 302:205-217) or programs based on these programs or algorithms are frequently used, for example. Sequence comparisons (alignments) using the computer program Vector NTI® Suite 10.3 (Invitrogen Corporation, 1600 Faraday Avenue, Carlsbad, Calif., USA) with the predetermined, default parameters, and the AlignX module of which for sequence comparisons is based on ClustalW, are also possible. Unless stated otherwise, the sequence identity given herein is determined by the BLAST algorithm.

Such a comparison also allows a statement regarding the similarity of the compared sequences. It is usually given in percent identity, i.e. the proportion of identical nucleotides or amino acid residues at the same positions or in an alignment of corresponding positions. The broader concept of homology takes conserved amino acid exchanges into account in the case of amino acid sequences, i.e. amino acids having similar chemical activity, since they usually perform similar chemical activities within the protein. Therefore, the similarity of the compared sequences may also be stated as percent homology or percent similarity. Identity and/or homology information can be provided regarding whole polypeptides or genes or only regarding individual regions. Homologous or identical regions of different nucleic acid or amino acid sequences are therefore defined by matches in the sequences. Such regions often have identical functions. They can be small and contain only a few nucleotides or amino acids. Often, such small regions perform essential functions for the overall activity of the protein. It may therefore be expedient to relate sequence matches only to individual, optionally small regions. Unless stated otherwise, however, identity or homology information in the present application relates to the entire length of the particular nucleic acid or amino acid sequence indicated.

The indication that an amino acid position corresponds to a numerically designated position in SEQ ID NO:1 means that the corresponding position is associated with the numerically designated position in SEQ ID NO:1 in an alignment as defined above.

In a further embodiment, the protease is characterized in that the cleaning performance thereof (after storage, e.g. over 3 weeks) is not significantly reduced compared with the wild-type enzyme (SEQ ID NO:1) or a starting variant (SEQ ID NO:2 from WO2013/060621A1), i.e. has at least 80% of the reference washing performance, such as at least 100%, for example at least 110% or more.

The cleaning performance can be determined in a washing system containing a washing agent in a dosage between 4.5 and 7.0 grams per liter of washing liquor, and the protease, the proteases to be compared being used in the same concentration (based on active protein), and the cleaning performance with respect to a stain on cotton is determined by measuring the degree of cleaning of the washed textiles. For example, the washing process can take place for 60 minutes at a temperature of 40° C. and the water can have a water hardness between 15.5 and 16.5° (German hardness). The concentration of the protease in the washing agent intended for this washing system is 0.001 to 0.1 wt. %, such as 0.01 to 0.06 wt. % based on active, purified protein.

A liquid reference washing agent for such a washing system may be composed for example as follows (all figures in wt. %): 4.4% alkyl benzene sulfonic acid, 5.6% further anionic surfactants, 2.4% 012-018 Na salts of fatty acids (soaps), 4.4% non-ionic surfactants, 0.2% phosphonates, 1.4% citric acid, 0.95% NaOH, 0.01% defoamer, 2% glycerol, 0.08% preservatives, 1% ethanol, and the remainder being demineralized water. In a non-limiting embodiment, the dosage of the liquid washing agent is between 4.5 and 6.0 grams per liter of washing liquor, for example 4.7, 4.9 or 5.9 grams per liter of washing liquor. Washing in a pH range between pH 7 and pH 10.5, such as between pH 7.5 and pH 8.5, may be possible.

The cleaning performance is determined for example at 20° C. or 40° C. using a liquid washing agent e.g. as stated above, the washing process may be carried out for 60 minutes at 600 rpm.

The degree of whiteness, i.e. the lightening of stains, as a measure of the cleaning performance is determined by optical measuring methods, such as photometrically. A suitable device for this purpose is for example the Minolta CM508d spectrometer. Usually, the devices used for the measurement are calibrated beforehand with a white standard, such as a supplied white standard.

A liquid reference hand dishwashing agent for such a washing system may be composed, for example, as follows (all figures in wt. %): 8-20% alkylbenzene sulfonic acid, 30-80% demineralized water, 5.4% NaOH (50%), 7.14% fatty alcohol ether sulfate, 2.0% NaCl (20%), 0.383% phosphoric acid (H3PO4; 34%/85%), 0.1% preservative, 0.25% perfume, 1.0% dye, 0.04% bitter principle.

The activity-equivalent use of the relevant protease ensures that the respective enzymatic properties, for example the cleaning performance on certain stains, are compared even if the ratio of active substance to total protein (the values of the specific activity) diverges. In general, a low specific activity can be compensated for by adding a larger amount of protein.

Otherwise, methods for determining protease activity are well known to, and routinely used by, a person skilled in the art of enzyme technology. For example, such methods are disclosed in Tenside, vol. 7 (1970), p. 125-132. Alternatively, the protease activity can be determined by the release of the chromophore para-nitroaniline (pNA) from the substrate suc-L-Ala-L-Ala-L-Pro-L-Phe-p-nitroanilide (AAPF). The protease cleaves the substrate and releases pNA. The release of the pNA causes an increase in absorbance at 410 nm, the temporal progression of which is a measure of the enzymatic activity (cf. Del Mar et al., 1979). The measurement is carried out at a temperature of 25° C., a pH of 8.6, and a wavelength of 410 nm. The measuring time is 5 min and the measuring interval is 20 s to 60 s. The protease activity is usually indicated in protease units (PE). Suitable protease activities amount to 2.25, 5 or 10 PE per ml of washing liquor, for example. However, the protease activity is not equal to zero.

An alternative test for establishing the proteolytic activity of the proteases is an optical measuring method, such as a photometric method. The appropriate test involves the protease-dependent cleavage of the substrate protein casein. This is cleaved by the protease into a multitude of smaller partial products. The totality of these partial products has an increased absorption at 290 nm compared with uncleaved casein, it being possible for this increased absorption to be determined using a photometer, and thus for a conclusion to be drawn regarding the enzymatic activity of the protease.

The protein concentration can be determined using known methods, for example the BCA method (bicinchoninic acid; 2,2′-bichinolyl-4,4′-dicarboxylic acid) or the Biuret method (Gornall et al., J. Biol. Chem. 177 (1948): 751-766). The active protein concentration can be determined in this regard by titrating the active centers using a suitable irreversible inhibitor and determining the residual activity (cf. Bender et al., J. Am. Chem. Soc. 88, 24 (1966): 5890-5913).

In addition to the amino acid alterations discussed above, proteases can have other amino acid alterations, in particular amino acid substitutions, insertions or deletions. Such proteases are, for example, developed by targeted genetic alteration, i.e. by mutagenesis methods, and optimized for specific applications or with regard to specific properties (for example with regard to their catalytic activity, stability, etc.). Furthermore, nucleic acids can be introduced into recombination approaches and can thus be used to generate completely novel proteases or other polypeptides.

The aim is to introduce targeted mutations such as substitutions, insertions or deletions into the known molecules in order, for example, to improve the cleaning performance of enzymes. For this purpose, in particular the surface charges and/or the isoelectric point of the molecules and thus their interactions with the substrate can be altered. For instance, the net charge of the enzymes can be altered in order to influence the substrate binding, in particular for use in washing and cleaning agents. Alternatively or additionally, one or more corresponding mutations can increase the stability or catalytic activity of the protease and thus improve its cleaning performance. Advantageous properties of individual mutations, e.g. individual substitutions, can complement one another. A protease which has already been optimized with regard to specific properties, for example with respect to its stability during storage, can therefore also be developed.

For the description of substitutions relating to exactly one amino acid position (amino acid exchanges), the following convention is used herein: first, the naturally occurring amino acid is designated in the form of the internationally used one-letter code, followed by the associated sequence position and finally the inserted amino acid. Several exchanges within the same polypeptide chain are separated by slashes. For insertions, additional amino acids are named following the sequence position. In the case of deletions, the missing amino acid is replaced by a symbol, for example a star or a dash, or a A is indicated before the corresponding position. For example, A95G describes the substitution of alanine at position 95 by glycine, A95AG the insertion of glycine after the amino acid alanine at position 95, and A95* or AA59 the deletion of alanine at position 95. This nomenclature is known to a person skilled in the field of enzyme technology.

A protease may be obtainable from a protease as described above as the starting molecule by one-time or multiple conservative amino acid substitution, the protease in the numbering according to SEQ ID NO:1 having at least one of the above-described amino acid substitutions. The term “conservative amino acid substitution” means the exchange (substitution) of one amino acid residue for another amino acid residue, with this exchange not resulting in a change to the polarity or charge at the position of the exchanged amino acid, e.g. the exchange of a nonpolar amino acid residue for another nonpolar amino acid residue. Conservative amino acid substitutions may include, for example: G=A=S, I=V=L=M, D=E, N=Q, K=R, Y=F, S=T, G=A=I=V=L=M=Y=F=W=P=S=T.

Alternatively or in addition, the protease is characterized in that it is obtainable from a protease as a starting molecule by fragmentation or deletion, insertion or substitution mutagenesis and comprises an amino acid sequence which matches the starting molecule over a length of at least 190, 200, 210, 220, 230, 240, 250, 260, 261, 262, 263, 264, 265, 266, 267, 268 or 269 contiguous amino acids, the protease having (i) at least two amino acid substitutions at at least two of the positions corresponding to positions 3, 4, 99 or 199, and (ii) at least one amino acid substitution at at least one of the positions corresponding to positions 74, 136, 143, 154, 161, 163, 171, 200, 203, 209, 212 or 256.

For instance, it is possible to delete individual amino acids at the termini or in the loops of the enzyme without the proteolytic activity being lost or diminished in the process. Furthermore, such fragmentation or deletion, insertion or substitution mutagenesis can also for example reduce the allergenicity of the enzymes concerned and thus improve their overall applicability. Advantageously, the enzymes retain their proteolytic activity even after mutagenesis, i.e. their proteolytic activity corresponds at least to that of the starting enzyme, i.e. in a non-limiting embodiment the proteolytic activity is at least 80%, such as at least 90% of the activity of the starting enzyme. Other substitutions can also exhibit advantageous effects. Both single and multiple contiguous amino acids can be exchanged for other amino acids.

The amino acid positions are in this case defined by an alignment of the amino acid sequence of a protease with the amino acid sequence of the protease from Bacillus lentus, as given in SEQ ID NO:1. Furthermore, the assignment of the positions depends on the mature protein. This assignment is also to be used in particular if the amino acid sequence of a protease comprises a higher or lower number of amino acid residues than the protease from Bacillus lentus according to SEQ ID NO:1. Proceeding from the above-mentioned positions in the amino acid sequence of the protease from Bacillus lentus, the alteration positions in a protease are those which are assigned to precisely these positions in an alignment.

Advantageous positions for sequence alterations, in particular substitutions, of the protease from Bacillus lentus, which are of particular significance when transferred to homologous positions of the proteases and which impart advantageous functional properties to the protease are therefore the positions which correspond to the positions described herein in an alignment, i.e. in the numbering according to SEQ ID NO:1. At the positions mentioned, the following amino acid residues are present in the wild-type molecule of the protease from Bacillus lentus (SEQ ID NO:1): N74, A136, R143, S154, Y161, A163, V171, Q200, Y203, A209, N212, L256.

Further confirmation of the correct assignment of the amino acids to be altered, i.e. in particular their functional correspondence, can be provided by comparative experiments, according to which the two positions assigned to one another on the basis of an alignment are modified in the same way in both compared proteases, and observations are made as to whether the enzymatic activity is modified in the same way in both cases. If, for example, an amino acid exchange in a specific position of the protease from Bacillus lentus according to SEQ ID NO:1 is accompanied by an alteration of an enzymatic parameter, for example an increase in the KM value, and a corresponding alteration of the enzymatic parameter, for example likewise an increase in the KM value, is observed in a protease variant of which the amino acid exchange has been achieved by the same introduced amino acid, this can therefore be considered to be confirmation of the correct assignment.

All of these aspects are also applicable to the method for producing a protease. Accordingly, a method further comprises one or more of the following method steps:

  • (a) introducing one-time or multiple conservative amino acid substitution into the protease, the protease having:
  • i) at least two amino acid substitutions at at least two of the positions corresponding to positions 3, 4, 99 or 199, and
  • ii) at least one amino acid substitution at at least one of the positions corresponding to positions 74, 136, 143, 154, 161, 163, 171, 200, 203, 209, 212 or 256;
  • (b) altering the amino acid sequence by fragmentation or deletion, insertion or substitution mutagenesis such that the protease comprises an amino acid sequence which matches the starting molecule over a length of at least 190, 200, 210, 220, 230, 240, 250, 260, 261, 262, 263, 264, 265, 266, 267, 268 or 269 contiguous amino acids, the protease having:
  • i) at least two amino acid substitutions at at least two of the positions corresponding to positions 3, 4, 99 or 199, and
  • ii) at least one amino acid substitution at at least one of the positions corresponding to positions 74, 136, 143, 154, 161, 163, 171, 200, 203, 209, 212 or 256.

All embodiments also apply to the methods.

In further embodiments, the protease or the protease prepared by means of a method is still at least 70%, 71%, 72%, 73%, 74%, 75%, 76%, 77%, 78%, 79%, 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 90.5%, 91%, 91.5%, 92%, 92.5%, 93%, 93.5%, 94%, 94.5%, 95%, 95.5%, 96%, 96.5%, 97%, 97.5%, 98%, 98.5%, 98.8%, 99% or 99.5% identical to the amino acid sequence given in SEQ ID NO:1 over its entire length. The protease or the protease prepared using a method has (i) at least two of the amino acid substitutions 3T, 4I, 99E or 199I at at least two of the positions corresponding to positions 3, 4, 99 or 199, and (ii) at least one of the amino acid substitutions 74D, 74E, 74Q, 136Q, 143L, 143W, 143Y, 154D, 154Q, 161T, 163G, 171L, 200A, 200L, 200S, 200T, 203K, 203V, 203W, 209W, 212N, 212S, 212T, 256D, 256E and 256Q at at least one of the positions corresponding to positions 74, 136, 143, 154, 161, 163, 171, 200, 203, 209, 212 or 256, in each case based on the numbering according to SEQ ID NO:1. Examples of this are the following amino acid substitution variants: (i) S3T+V4I+R99E+V199I+Q200L+Y203W; (ii) S3T+V4I+R99E+V199I+N212S; (iii) S3T+V4I+R99E+V199I+N74D; (iv) S3T+V4I+R99E+V199I+S154D+L256E; (v) S3T+V4I+R99E+V199I+Q200L+Y203W+S154D+L256E; (vi) S3T+V4I+R99E+V199I+N74D+Q200L+Y203W; (vii) S3T+V4I+R99E+V199I+N74D+S154D+Q200L+Y203W+L256E; (viii) S3T+V4I+R99E+V199I+N74D+N212S; (ix) S3T+V4I+R99E+V199I+N74D+S154D+Y203W+L256E; (x) S3T+V4I+R99E+V199I+N74D+Y203W; (xi) S3T+V4I+R99E+V199I+N74D+S154D+Q200L+L256E; (xii) S3T+V4I+R99E+V199I+N74D+Q200L; (xiii) S3T+V4I+R99E+V199I+S154D+Q200L+Y203W; (xiv) S3T+V4I+R99E+V199I+Q200L+Y203W+L256E; (xv) S3T+V4I+R99E+V199I+A136Q+R143W+Y161T+Q200L; (xvi) S3T+V4I+R99E+V199I+N74D+R143Y+A209W+N212S+L256E; (xvii) S3T+V4I+R99E+V199I+A136Q+S154D+V171L+Q200L, in each case based on the numbering according to SEQ ID NO: 1, and the variants described in the examples.

The protease may also be stabilized, in particular by one or more mutations, for example substitutions, or by coupling to a polymer. An increase in stability during storage and/or during use, for example in the washing process, leads to longer enzymatic activity and thus improves the cleaning performance. In principle, all stabilization options which are described in the prior art and/or are appropriate are considered. Those stabilizations may be used which are achieved by mutations of the enzyme itself, since such stabilizations do not require any further work steps following the recovery of the enzyme. Examples of sequence alterations suitable for this purpose are mentioned above. Further suitable sequence alterations are known from the prior art.

Further possibilities for stabilization are, for example:

    • altering the binding of metal ions, in particular the calcium binding sites, for example by exchanging one or more of the amino acid(s) that are involved in the calcium binding with one or more negatively charged amino acids and/or by introducing sequence alterations in at least one of the sequences of the two amino acids arginine/glycine;
    • protecting against the influence of denaturing agents such as surfactants by mutations that cause an alteration of the amino acid sequence on or at the surface of the protein;
    • exchanging amino acids near the N-terminus with those likely to contact the rest of the molecule via non-covalent interactions, and thus contributing to the maintenance of the globular structure.

Non-limiting embodiments are those in which the enzyme is stabilized in several ways, as several stabilizing mutations act additively or synergistically.

A protease may have at least one chemical modification. A protease with such an alteration is referred to as a derivative, i.e. the protease is derivatized.

In the context of the present application, derivatives are thus understood to mean those proteins of which the pure amino acid chain has been chemically modified. Such derivatizations can be achieved, for example, in vivo by the host cell that expresses the protein. In this regard, couplings of low-molecular-weight compounds such as lipids or oligosaccharides are particularly noteworthy. However, the derivatizations may also be carried out in vitro, for example by the chemical conversion of a side chain of an amino acid or by covalent bonding of another compound to the protein. For example, it is possible to couple amines to carboxyl groups of an enzyme in order to alter the isoelectric point. Another such compound may also be another protein that is bound to a protein via bifunctional chemical compounds, for example. Derivatization is also understood to mean the covalent bonding to a macromolecular carrier or a non-covalent inclusion in suitable macromolecular cage structures. Derivatizations may, for example, affect the substrate specificity or bonding strength to the substrate or cause a temporary blockage of the enzymatic activity when the coupled substance is an inhibitor. This can be expedient, for example, for the period of storage. Such modifications may further affect the stability or enzymatic activity. They can also be used to reduce the allergenicity and/or immunogenicity of the protein and thus, for example, increase its skin compatibility. For example, couplings with macromolecular compounds, for example polyethylene glycol, can improve the protein in terms of stability and/or skin compatibility.

Derivatives of a protein can also be understood in the broadest sense to mean preparations of these proteins. Depending on the recovery, processing or preparation, a protein can be combined with various other substances, for example from the culture of the producing microorganisms. A protein may also have been deliberately added to other substances, for example to increase its storage stability. Therefore, all preparations of a protein are also in accordance with the invention. This is also irrespective of whether or not it actually exhibits this enzymatic activity in a particular preparation. This is because it may be desired that it has no or only low activity during storage, and exhibits its enzymatic function only at the time of use. This can be controlled via appropriate accompanying substances, for example. In particular, the joint preparation of proteases with specific inhibitors is possible in this regard.

Of all the proteases or protease variants and/or derivatives described above, those of which the storage stability and/or the cleaning performance is improved compared with the starting variant may be used, the cleaning performance being determined in a washing system as described above.

A nucleic acid may code for a protease, as well as to a vector containing such a nucleic acid, in particular a cloning vector or an expression vector.

These may be DNA or RNA molecules. They can be present as a single strand, as a single strand that is complementary to this single strand, or as a double strand. In particular in the case of DNA molecules, the sequences of the two complementary strands must be taken into account in all three possible reading frames. Furthermore, it should be noted that different codons, i.e. base triplets, can code for the same amino acids such that a particular amino acid sequence can be coded by a plurality of different nucleic acids. Due to this degeneracy of the genetic code, all of the nucleic acid sequences which can code any of the proteases described above are useable. A person skilled in the art is able to determine these nucleic acid sequences unequivocally since, despite the degeneracy of the genetic code, defined amino acids can be assigned to individual codons. Therefore, a person skilled in the art proceeding from an amino acid sequence can easily determine nucleic acids coding for said amino acid sequence. Furthermore, in the case of nucleic acids, one or more codons may be replaced by synonymous codons. This aspect relates in particular to the heterologous expression of the enzymes. For instance, every organism, for example a host cell of a production strain, has a particular codon usage. Codon usage is understood to mean the translation of the genetic code into amino acids by the relevant organism. Bottlenecks can occur in the protein biosynthesis if the codons on the nucleic acid in the organism are faced with a comparatively small number of loaded tRNA molecules. Although coding for the same amino acid, this results in a codon being translated less efficiently in the organism than a synonymous codon coding for the same amino acid. Due to the presence of a higher number of tRNA molecules for the synonymous codon, it can be translated more efficiently in the organism.

Using methods which are currently generally known, such as chemical synthesis or the polymerase chain reaction (PCR), in conjunction with molecular-biological and/or protein-chemical standard methods, it is possible for a person skilled in the art to produce the corresponding nucleic acids and even complete genes on the basis of known DNA and/or amino acid sequences. Such methods are known, for example, from Sambrook, J., Fritsch, E. F. and Maniatis, T. 2001. Molecular cloning: a laboratory manual, 3rd edition, Cold Spring Laboratory Press.

Vectors are understood to mean elements consisting of nucleic acids, which elements contain a nucleic acid as the characteristic nucleic acid region. They are able to establish these as a stable genetic element in a species or cell line over several generations or cell divisions. Vectors are special plasmids, i.e. circular genetic elements, in particular when used in bacteria. A nucleic acid may be cloned into a vector. The vectors include, for example, those originating from bacterial plasm ids, viruses or bacteriophages, or predominantly synthetic vectors or plasm ids with elements of a wide variety of origins. With the additional genetic elements present in each case, vectors are able to establish themselves as stable units in the corresponding host cells over several generations. They may be present as separate units in an extrachromosomal manner or integrated into a chromosome or chromosomal DNA.

Expression vectors comprise nucleic acid sequences which enable them to replicate in the host cells containing them, such as microorganisms, for example bacteria, and to express a contained nucleic acid there. The expression is in particular influenced by the promoter(s) that regulate the transcription. In principle, the expression can take place by the natural promoter originally located before the nucleic acid to be expressed, but also by a promoter of the host cell provided on the expression vector or also by a modified or completely different promoter of another organism or another host cell. In the present case, at least one promoter is provided for the expression of a nucleic acid and used for the expression thereof. Furthermore, expression vectors can be regulatable, for example by changing the cultivation conditions or when a specific cell density of the host cells containing them is reached or by addition of specific substances, in particular activators of gene expression. An example of such a substance is the galactose derivative isopropyl-β-D-thiogalactopyranoside (IPTG), which is used as an activator of the bacterial lactose operon (lac operon). In contrast with expression vectors, the nucleic acid contained is not expressed in cloning vectors.

A non-human host cell may include a nucleic acid or a vector or contain a protease, in particular one which secretes the protease into the medium surrounding the host cell. In non-limiting embodiments, a nucleic acid or a vector is transformed into a microorganism, which then represents a host cell. Alternatively, individual components, i.e. nucleic acid parts or fragments of a nucleic acid, can be introduced into a host cell such that the resulting host cell contains a nucleic acid or a vector. This procedure is particularly suitable when the host cell already contains one or more constituents of a nucleic acid or a vector and the further constituents are then supplemented accordingly. Methods for transforming cells are established in the prior art and are well known to a person skilled in the art. In principle, all cells, i.e. prokaryotic or eukaryotic cells, are suitable as host cells. Host cells that can be managed in a genetically advantageous manner, for example in terms of the transformation with the nucleic acid or the vector and the stable establishment thereof, may be used, for example unicellular fungi or bacteria. Furthermore, host cells are characterized by good microbiological and biotechnological manageability. This relates, for example, to easy cultivation, high growth rates, low requirements for fermentation media and good production and secretion rates for foreign proteins. Non-limiting host cells secrete the (transgenically) expressed protein into the medium surrounding the host cells. Furthermore, the proteases can be modified by the cells producing them after their production, for example by attachment of sugar molecules, formylations, aminations, etc. Such post-translational modifications can functionally influence the protease.

Other embodiments are those host cells of which the activity can be regulated on account of genetic regulatory elements, which are, for example, made available on the vector but may also be present in these cells from the outset. These host cells may be induced to express for example by the controlled addition of chemical compounds which are used as activators, by modifying the cultivation conditions, or when a specific cell density is reached. This enables economical production of the proteins. An example of such a compound is IPTG as described above.

Prokaryotic or bacterial cells may act as host cells. Bacteria are characterized by short generation times and low demands on cultivation conditions. As a result, cost-effective cultivation methods or production methods can be established. In addition, a person skilled in the art has a wealth of experience in the case of bacteria in fermentation technology. For a specific production, gram-negative or gram-positive bacteria may be suitable for a wide variety of reasons to be determined experimentally in individual cases, such as nutrient sources, product formation rate, time requirement, etc.

In the case of gram-negative bacteria, such as Escherichia coli, a large number of proteins are secreted into the periplasmic space, i.e. into the compartment between the two membranes enclosing the cells. This may be advantageous for particular applications. Furthermore, gram-negative bacteria can also be designed such that they eject the expressed proteins not only into the periplasmic space, but into the medium surrounding the bacterium. In contrast, gram-positive bacteria such as bacilli or actinomycetes or other representatives of Actinomycetales have no outer membrane, and therefore secreted proteins are released immediately into the medium surrounding the bacteria, usually the nutrient medium, from which the expressed proteins can be purified. They can be isolated directly from the medium or further processed. In addition, gram-positive bacteria are related or identical to most of the origin organisms for technically significant enzymes and usually even form comparable enzymes, meaning that they have a similar codon usage and the protein synthesizer is naturally aligned accordingly.

Host cells may be altered in terms of their requirements for the culture conditions, may have different or additional selection markers or may express other or additional proteins. In particular, this may also involve those host cells which transgenically express several proteins or enzymes.

The present invention is applicable in principle to all microorganisms, in particular to all fermentable microorganisms, such as those of the genus Bacillus, and leads to it being possible to produce proteins by the use of such microorganisms. Such microorganisms may represent host cells.

In a further embodiment, the host cell is characterized in that it is a bacterium, such as one selected from the group of the genera of Escherichia, Klebsiella, Bacillus, Staphylococcus, Corynebacterium, Arthrobacter, Streptomyces, Stenotrophomonas and Pseudomonas, for example one selected from the group of Escherichia coli, Klebsiella planticola, Bacillus licheniformis, Bacillus lentus, Bacillus amyloliquefaciens, Bacillus subtilis, Bacillus alcalophilus, Bacillus globigii, Bacillus gibsonii, Bacillus clausii, Bacillus halodurans, Bacillus pumilus, Staphylococcus carnosus, Corynebacterium glutamicum, Arthrobacter oxidans, Streptomyces lividans, Streptomyces coelicolor and Stenotrophomonas maltophilia.

The host cell may also be a eukaryotic cell, however, which is characterized in that it has a cell nucleus. A host cell may have a cell nucleus. In contrast with prokaryotic cells, eukaryotic cells are capable of post-translationally modifying the protein formed. Examples thereof are fungi such as Actinomycetes or yeasts such as Saccharomyces or Kluyveromyces. This can be particularly advantageous, for example, if the proteins are to undergo specific modifications in connection with their synthesis that make such systems possible. Modifications carried out by eukaryotic systems, in particular in connection with the protein synthesis, include, for example, the binding of low-molecular-weight compounds such as membrane anchors or oligosaccharides. Such oligosaccharide modifications may be desirable, for example, to lower the allergenicity of an expressed protein. Co-expression with the enzymes naturally formed by such cells, such as cellulases, may be advantageous. Furthermore, for example, thermophilic fungal expression systems may be particularly suitable for the expression of temperature-resistant proteins or variants.

The host cells are cultivated and fermented in the conventional way, for example in discontinuous or continuous systems. In the first case, a suitable nutrient medium is inoculated with the host cells and the product is harvested from the medium after a period to be determined experimentally. Continuous fermentations are characterized by the achievement of a flow equilibrium, in which cells partially die over a comparatively long period of time but also grow back and the protein formed can be removed from the medium at the same time.

Host cells are used to produce proteases. A method for preparing a protease, may include

a) cultivating a host cell, and

b) isolating the protease from the culture medium or from the host cell.

This method may include fermentation processes. Fermentation processes are known per se from the prior art and represent the actual large-scale production step, usually followed by a suitable purification method of the prepared product, for example the proteases. All fermentation processes which are based on a corresponding method for producing a protease may be used.

Fermentation processes which are characterized in that the fermentation is carried out via a feed strategy shall be considered in particular. In this case, the media constituents that are consumed by the continuous cultivation are added. As a result, considerable increases can be achieved both in the cell density and in the cell mass or dry mass and/or in particular in the activity of the protease of interest. Furthermore, the fermentation can also be designed in such a way that undesired metabolic products are filtered out or neutralized by adding buffers or suitable counter ions.

The produced protease can be harvested from the fermentation medium. Such a fermentation process is better than isolation of the protease from the host cell, i.e. product preparation from the cell mass (dry matter), but requires the provision of suitable host cells or one or more suitable secretion markers or mechanisms and/or transport systems for the host cells to secrete the protease into the fermentation medium. Without secretion, the protease can alternatively be isolated from the host cell, i.e. purified from the cell mass, for example by precipitation with ammonium sulphate or ethanol, or by chromatographic purification.

All of the above-mentioned aspects can be combined into methods in order to produce a protease.

An agent may include a protease as described above. The agent may be a washing or cleaning agent.

The agent may include all types of washing or cleaning agents, both concentrates and undiluted agents, for use on a commercial scale, in washing machines or for hand washing or cleaning. These include, for example, washing agents for textiles, carpets, or natural fibers, for which the term washing agent is used. These include, for example, dishwashing detergents for dishwashers or manual dishwashing detergents or cleaners for hard surfaces such as metal, glass, porcelain, ceramics, tiles, stone, painted surfaces, plastics, wood or leather, for which the term cleaning agent is used, i.e. in addition to manual and mechanical dishwashing detergents, also, for example, scouring agents, glass cleaners, WC toilet scenters, etc. The washing and cleaning agents also include auxiliary washing agents which are added to the actual washing agent during manual or automatic textile washing in order to achieve a further effect. Furthermore, washing and cleaning agents also include textile pre-treatment and post-treatment agents, i.e. those agents with which the item of laundry is brought into contact before the actual washing cycle, for example to loosen stubborn soiling, and also those agents which give the laundry further desirable properties such as a pleasant feel, crease resistance or low static charge in a step subsequent to the actual textile wash. Inter alia, softeners are included in the last-mentioned agents.

The washing or cleaning agents may be in the form of powdered solids, in further-compacted particulate form, as gels, homogeneous solutions or suspensions, may contain, in addition to a protease, all known ingredients conventional in such agents, with at least one further ingredient being present in the agent. The agents may in particular contain surfactants, builders, peroxygen compounds or bleach activators. They may also contain water-miscible organic solvents, further enzymes, sequestering agents, electrolytes, pH regulators and/or further auxiliaries such as optical brighteners, graying inhibitors, foam regulators, as well as dyes and fragrances, and combinations thereof.

In particular, a combination of a protease with one or more further ingredients of the agent is advantageous, since, in embodiments, such an agent has improved cleaning performance by virtue of resulting synergisms. In particular, combining a protease with a surfactant and/or a builder and/or a peroxygen compound and/or a bleach activator can result in such a synergism. However, in embodiments, the agent may not contain boric acid.

Advantageous ingredients of agents are disclosed in international patent application WO2009/121725A1, starting at the penultimate paragraph of page 5 and ending after the second paragraph on page 13. Reference is expressly made to this disclosure and the disclosure therein is incorporated in the present patent application by reference.

An agent advantageously contains the protease in an amount of from 2 μg to 20 mg, such as from 5 μg to 17.5 mg, for example from 20 μg to 15 mg, i.e. from 50 μg to 10 mg per g of the agent. In various embodiments, the concentration of the protease (active enzyme) described herein in the agent is >0 to 1 wt. %, such as 0.001 to 0.1 wt. %, based on the total weight of the agent or composition. Further, the protease contained in the agent, and/or further ingredients of the agent, may be coated with a substance which is impermeable to the enzyme at room temperature or in the absence of water, and which becomes permeable to the enzyme under conditions of use of the agent. The protease may be coated with a substance which is impermeable to the protease at room temperature or in the absence of water. Furthermore, the washing or cleaning agent itself may also be packaged in a container, such as an air-permeable container, from which it is released shortly before use or during the washing process.

In further embodiments, the agent is characterized in that it

  • (a) is present in solid form, in particular as a flowable powder having a bulk density of from 300 g/l to 1200 g/l, in particular from 500 g/l to 900 g/l, or
  • (b) is present in pasty or liquid form, and/or
  • (c) is present in the form of a gel or in the form of dosing pouches, and/or
  • (d) is present as a single-component system, or
  • (e) is divided into a plurality of components.

These embodiments include all solid, powdered, liquid, gel or pasty administration forms of agents, which may optionally also consist of a plurality of phases and can be present in compressed or uncompressed form. The agent may be present as a flowable powder, in particular having a bulk density of from 300 g/l to 1200 g/l, in particular from 500 g/l to 900 g/l or from 600 g/l to 850 g/l. The solid administration forms of the agent also include extrudates, granules, tablets or pouches. Alternatively, the agent may also be in liquid, gel or pasty form, for example in the form of a non-aqueous liquid washing agent or a non-aqueous paste or in the form of an aqueous liquid washing agent or a water-containing paste. Liquid agents are generally possible. The agent may also be present as a one-component system. Such agents consist of one phase. Alternatively, an agent may also consist of a plurality of phases. Such an agent is therefore divided into a plurality of components.

Washing or cleaning agents may contain only one protease. Alternatively, they may also contain other hydrolytic enzymes or other enzymes in a concentration that is expedient for the effectiveness of the agent. A further embodiment is therefore represented by agents which further comprise one or more further enzymes. Further enzymes can be used that exhibit catalytic activity in the agent, in particular a lipase, amylase, cellulase, hemicellulase, mannanase, tannase, xylanase, xanthanase, xyloglucanase, β-glucosidase, pectinase, carrageenase, perhydrolase, oxidase, oxidoreductase or another protease, which may be different from the proteases, as well as mixtures thereof. Further enzymes are advantageously contained in the agent in an amount of from 1×10−8 to 5 wt. % based on active protein. Each further enzyme is contained in agents in an amount of from 1×10−7 to 3 wt. %, from 0.00001 to 1 wt. %, from 0.00005 to 0.5 wt. %, from 0.0001 to 0.1 wt. % and such as from 0.0001 to 0.05 wt. %, in each case based on active protein. In non-limiting embodiments, the enzymes exhibit synergistic cleaning performance on specific stains or spots, i.e. the enzymes contained in the agent composition support one another in their cleaning performance. In non-limiting embodiments, there is such synergism between the protease contained and a further enzyme of an agent, including in particular between said protease and an amylase and/or a lipase and/or a mannanase and/or a cellulase and/or a pectinase. Synergistic effects can arise not only between different enzymes, but also between one or more enzymes and other ingredients of the agent.

In the cleaning agents described herein, the enzymes to be used may furthermore be formulated together with accompanying substances, for example from fermentation. In liquid formulations, the enzymes are used as enzyme liquid formulations.

The enzymes are generally not provided in the form of pure protein, but rather in the form of stabilized, storable and transportable preparations. These pre-formulated preparations include, for example, the solid preparations obtained through granulation, extrusion, or lyophilization or, particularly in the case of liquid or gel agents, solutions of the enzymes, which are advantageously maximally concentrated, have a low water content, and/or are supplemented with stabilizers or other auxiliaries.

Alternatively, the enzymes can also be encapsulated, for both the solid and the liquid administration form, for example by spray-drying or extrusion of the enzyme solution together with a natural polymer or in the form of capsules, for example those in which the enzymes are enclosed in a set gel, or in those of the core-shell type, in which an enzyme-containing core is coated with a water-, air-, and/or chemical-impermeable protective layer. In the case of overlaid layers, other active ingredients, such as stabilizers, emulsifiers, pigments, bleaching agents, or dyes, can be additionally applied. Such capsules are applied using inherently known methods, for example by shaking or roll granulation or in fluidized bed processes. Such granules are advantageously low in dust, for example due to the application of polymeric film-formers, and stable in storage due to the coating.

Moreover, it is possible to formulate two or more enzymes together, such that a single granule exhibits a plurality of enzyme activities.

The enzymes can also be incorporated in water-soluble films, such as those used in the formulation of washing and cleaning agents in a unit dosage form. Such a film allows the release of the enzymes following contact with water. As used herein, “water-soluble” refers to a film structure that is completely water-soluble. In non-limiting embodiments, such a film consists of (fully or partially hydrolyzed) polyvinyl alcohol (PVA).

A method for cleaning textiles or hard surfaces may occur by using an agent in at least one method step, or in that a protease becomes catalytically active in at least one method step, in particular such that the protease is used in an amount of from 40 μg to 4 g, such as from 50 μg to 3 g, for example from 100 μg to 2 g, and i.e. from 200 μg to 1 g or in the concentrations described herein.

In various embodiments, the method described above is characterized in that the protease is used at a temperature of from 0 to 100° C., such as 0 to 60° C., for example 20 to 40° C., i.e. at 25° C.

These include both manual and mechanical methods. Methods for cleaning textiles are generally characterized by the fact that, in a plurality of method steps, various cleaning-active substances are applied to the material to be cleaned and washed off after the exposure time, or in that the material to be cleaned is otherwise treated with a washing agent or a solution or dilution of this agent. The same applies to methods for cleaning all materials other than textiles, in particular hard surfaces. All conceivable washing or cleaning methods can be enhanced in at least one of the method steps by the use of a washing or cleaning agent or a protease. Therefore, reference is expressly made at this point to the disclosure at the appropriate point with the note that this disclosure also applies to the above-described methods.

Since proteases naturally already have hydrolytic activity and also exhibit this in media which otherwise have no cleaning power, for example in a simple buffer, a single and/or the sole step of such a method can consist in a protease, which is the only cleaning-active component, being brought into contact with the stain, such as in a buffer solution or in water.

Alternative embodiments are also represented by methods for treating textile raw materials or for textile care, in which a protease becomes active in at least one method step. Among these, methods for textile raw materials, fibers or textiles with natural components may be used, and especially for those with wool or silk.

Finally, the proteases described herein may be used in washing or cleaning agents, for example as described above, for the (improved) removal of protein-containing stains, for example from textiles or hard surfaces. In embodiments of this use, the protease in the washing or cleaning agent is stored for 3 or more days, 4 or more days, 7 or more days, 10 or more days, 12 or more days, 14 or more days, 21 or more days or 28 or more days before a washing or cleaning process.

All aspects, objects, and embodiments described for the protease and agents containing it are also applicable to this subject matter of the invention. Therefore, reference is expressly made at this point to the disclosure at the appropriate point with the note that this disclosure also applies to the above-described use.

EXAMPLES Example 1: Overview of the Mutations

A subtilisin-type alkaline protease from Bacillus lentus is disclosed. From a starting variant (protease according to SEQ ID NO:2 from WO2013/060621A1), variants were produced by random mutagenesis, which were then screened, inter alia for improved washing performance and/or enzyme stability. In this way, 17 mutants having improved storage stability and/or improved cleaning performance were generated from said protease.

Variant Amino acid substitutions relative to SEQ ID NO: 1 Starting S3T V4I R99E V199I variant Mutant 1 S3T V4I R99E V199I Q200L Y203 Mutant 2 S3T V4I R99E V199I N212S Mutant 3 S3T V4I R99E V199I N74D Mutant 4 S3T V4I R99E V199I S154D L256E Mutant 5 S3T V4I R99E V199I S154D Q200L Y203 L256E Mutant 6 S3T V4I R99E V199I N74D Q200L Y203 Mutant 7 S3T V4I R99E V199I N74D S154D Q200L Y203W L256E Mutant 8 S3T V4I R99E V199I N74D N212S Mutant 9 S3T V4I R99E V199I N74D S154D Y203 L256E Mutant 10 S3T V4I R99E V199I N74D Y203 Mutant 11 S3T V4I R99E V199I N74D S154D Q200L L256E Mutant 12 S3T V4I R99E V199I N74D Q200L Mutant 13 S154D Q200L Y203W Mutant 14 Q200L Y203 L256E Mutant 15 A136Q R143 Y161T Q200 Mutant 16 N74D R143Y Y203W N212 L256 Mutant 17 A136Q S154D V171L Q200

Washing Agent Matrix Used

Wt. % of active Wt. % of active substance in the substance the Chemical name raw material formulation Demineralized water 100 Remainder Alkyl benzene sulfonic acid 96  9-18 Anionic surfactants 70 3-8 C12-C18 fatty acid Na salt 30 2-4 Non-ionic surfactants 100  5-14 Phosphonate 60 0.5-2  Citric acid 100 3-5 NaOH 50 0.5-2  Defoamer 100 <1% Glycerol 99.5 1-3 1,2-propanediol 100  8-12 Monoethanolamine 100 4-8 Soil repellent polymer 30 0.5-1  Protease stabilizer 100 0.5-1.5 Without opt. brighteners, perfume, dye and enzymes. Dosage 3.17 g/L

Example 2: Determining Storage Stability

Storage

The proteases are present in bioreactor-generated supernatants in Bacillus licheniformis. They are diluted to an equal level of activity. 90% washing agent matrix without boric acid was added to 10% of appropriately diluted Bacillus licheniformis supernatant and mixed well. The sealed vessels were stored at 40° C. for four weeks. The amount of sample removed was dissolved for 20 minutes at room temperature in 0.1 M Tris/HCl (pH 8.6) by stirring. The AAPF assay was then carried out as described below.

Protease Activity Assay

The activity of the protease is determined by the release of the chromophore para-nitroaniline from the substrate succinyl alanine-alanine-proline-phenylalanine-para-nitroanilide (AAPFpNA; Bachem L-1400). The release of the pNA causes an increase in absorbance at 410 nm, the temporal progression of which is a measure of the enzymatic activity.

The measurement was carried out at a temperature of 25° C., a pH of 8.6, and a wavelength of 410 nm. The measuring time was 5 minutes with a measuring interval of from 20 to 60 seconds.

Measurement approach:

10 μL AAPF solution (70 mg/mL)

1000 μl Tris/HCl (0.1 M, pH 8.6 with 0.1% Brij 35)

10 μL diluted protease solution

Kinetics created over 5 min at 25° C. (410 nm)

The residual activity in % of the residual activity of the starting variant after 4 weeks' storage at 40° C. in the abovementioned washing agent matrix is shown below:

Variant Residual activity (in Starting variant Mutant 1 +29 Mutant 2 +9 Mutant 3 +9 Mutant 4 +4 Mutant 5 +60

Variants 1, 2 and 3, 4 exhibit a higher residual activity in comparison with the starting variant.

Example 3: Determining Cleaning Performance

Mini Washing Test

Washing test with Bacillus subtilis culture supernatants containing the screened protease mutants by heterologous expression. The supernatants are used in washing agents in the equivalent activity to the benchmark=starting variant at a market-standard concentration for proteases. In contrast to determining storage stability, the samples are not stored, but the cleaning performance is determined directly. The mutants are all based on the washing performance of the starting variant, which is set to be equal to 100%.

Conditions: 40° C., 16° dH water, 1 h

Stain: CFT CS038

Punched-out pieces of fabric (diameter=10 mm) were provided in microtiter plates, the washing liquor was pre-heated to 40° C., final concentration 3.17 g/L, the liquor and enzyme were added to the stain, were incubated for 1 h at 40° C. and 600 rpm, then the stain was rinsed several times with clear water, left to dry and the brightness was determined using a color-measuring device. The brighter the fabric, the better the cleaning performance. The L value=brightness is measured here, and the higher the brighter. Performance is given in % based on the starting variant corrected by the performance of the washing agent without protease.

Performance in the washing test at 40° C. Variant (based on performance of the starting variant) Starting variant 100% Mutant 1 105% Mutant 5 109%

Variants 1 and 5 exhibit increased washing performance in comparison with the starting variant.

Proteases, in particular variants 1 and 5, therefore demonstrate not only improved storage stability but also improved cleaning performance.

Claims

1. A protease comprising an amino acid sequence having at least 70% sequence identity to SEQ ID NO:1, wherein the protease comprises:

i) first amino acid substitutions at positions corresponding to positions 3, 4, 99, and 199 and selected from the group consisting of 3T, 4I, 99E, and 199I; and
ii) two or more second amino acid substitution at positions corresponding to positions 74, 136, 143, 154, 161, 163, 171, 200, 203, 209, 212, 256, or combinations thereof.

2. The protease according to claim 1, wherein

the two or more second amino acid substitutions at positions corresponding to positions 74, 136, 143, 154, 161, 163, 171, 200, 203, 209, 212, 256, or combinations is selected from the group consisting of 74D, 74E, 74Q, 136Q, 143L, 143W, 143Y, 154D, 154Q, 161T, 163G, 171L, 200A, 200L, 200S, 200T, 203K, 203V, 203W, 209W, 212N, 212S, 212T and 256D, 256E, 256Q, or combinations thereof.

3. The protease according to claim 1, wherein:

the two or more second amino acid substitution comprise one or more of the following combinations: Q200L+Y203W; S154D+L256E; Q200L+Y203W+S154D+L256E; N74D+Q200L+Y203W; N74D+S154D+Q200L+Y203W+L256E; N74D+N212 S; (ix) N74D+S154D+Y203W+L256E; N74D+Y203W; N74D+S154D+Q200L+L256E; N74D+Q200L; S154D+Q200L+Y203W; Q200L+Y203W+L256E; A136Q+R143W+Y161T+Q200L; N74D+R143Y+A209W+N212S+L256E; A136Q+S154D+V171L+Q200L.

4. The protease according to claim 1, wherein: the two or more second amino acid substitutions comprises one or more of the following amino acid substitution combinations: (i) Q200L+Y203W; (ii) N212S; (iii) N74D; (iv) S154D+L256E; (v) Q200L+Y203W+S154D+L256E; (vi) N74D+Q200L+Y203W; (vii) N74D+S154D+Q200L+Y203W+L256E; (viii) N74D+N212S; (ix) N74D+S154D+Y203W+L256E; (x) N74D+Y203W; (xi) N74D+S154D+Q200L+L256E; (xii) N74D+Q200L; (xiii) S154D+Q200L+Y203W; (xiv) Q200L+Y203W+L256E; (xv) A136Q+R143W+Y161T+Q200L; (xvi) N74D+R143Y+A209W+N212S+L256E; (xvii) A136Q+S154D+V171L+Q200L.

5. The protease according to claim 1, wherein the protease consists of:

i) first amino acid substitutions at positions corresponding to positions 3, 4, 99, and 199 and selected from the group consisting of 3T, 4I, 99E, and 199I; and
ii) two or more second amino acid substitution at positions corresponding to positions 74, 136, 143, 154, 161, 163, 171, 200, 203, 209, 212, 256, or combinations thereof.

6. The protease according to claim 1, wherein the protease comprises three or more second amino acid substitution at positions corresponding to positions 74, 136, 143, 154, 161, 163, 171, 200, 203, 209, 212, 256, or combinations thereof.

7. The protease according to claim 1, wherein the protease comprises four or more second amino acid substitution at positions corresponding to positions 74, 136, 143, 154, 161, 163, 171, 200, 203, 209, 212, 256, or combinations thereof.

8. The protease according to claim 1, wherein two or more second amino acid substitutions occur at least at positions 200 and 203.

9. A washing agent composition or cleaning agent composition comprising at least one protease according to claim 1.

10. A protease comprising an amino acid sequence having at least 70% sequence identity to SEQ ID NO:1, wherein the protease consists of:

first amino acid substitutions at positions corresponding to positions 3, 4, 99, 199 and selected from the group consisting of 3T, 4I, 99E, and 199I; and
one or more second amino acid substitution at positions corresponding to positions 74, 136, 143, 161, 163, 171, 200, 203, 209, 212, 256, or combinations thereof.

11. A method for preparing a protease, comprising:

introducing first amino acid substitutions into a starting molecule having an amino acid sequence having at least 70% sequence identity with the amino acid sequence given in SEQ ID NO:1 over its entire length; wherein the first amino acid substitutions occur at positions corresponding to positions 3, 4, 99, 199, and selected from the group consisting of 3T, 4I, 99E and 199I; and
introducing two or more second amino acid substitution into a starting molecule having an amino acid sequence having at least 70% sequence identity with the amino acid sequence given in SEQ ID NO:1 over its entire length; wherein the two or more second amino acid substitutions occur at positions corresponding to the positions 74, 136, 143, 154, 161, 163, 171, 200, 203, 209, 212, 256, or combinations thereof.

12. The method according to claim 11, further comprising altering the amino acid sequence by fragmentation or deletion, insertion or substitution mutagenesis such that the protease comprises an amino acid sequence which matches the starting molecule over a length of at least 190 contiguous amino acids.

13. A nucleic acid coding for a protease according to claim 1.

14. A vector containing a nucleic acid according to claim 13.

15. A non-human host cell that contains a vector according to claim 14.

16. A method for preparing a protease, comprising

a) cultivating a host cell according to claim 15; and
b) isolating the protease from the culture medium or from the host cell.
Referenced Cited
U.S. Patent Documents
5340735 August 23, 1994 Christianson et al.
20120238005 September 20, 2012 Wieland et al.
20140018282 January 16, 2014 Wieland et al.
20140227764 August 14, 2014 Hellmuth et al.
20150017707 January 15, 2015 Mussmann et al.
20160186159 June 30, 2016 O'Connell et al.
20160237418 August 18, 2016 Hellmuth et al.
20170037343 February 9, 2017 Hellmuth et al.
20170175098 June 22, 2017 Pedersen et al.
20180216040 August 2, 2018 Baltsen et al.
20180298368 October 18, 2018 Raab et al.
20200032170 January 30, 2020 Oehlenschlaeger
Foreign Patent Documents
102004027091 December 2005 DE
3044302 July 2016 EP
9221760 December 1992 WO
9523221 August 1995 WO
2009121725 October 2009 WO
2011032988 March 2011 WO
2012080202 June 2012 WO
2013060621 May 2013 WO
2015036152 March 2015 WO
2015044206 April 2015 WO
2015055477 April 2015 WO
2016096714 June 2016 WO
2018011277 January 2018 WO
2018069158 April 2018 WO
Other references
  • UniProt AOA060M6U8—Bacillus lehensis G1 protease, deposited Sep. 2014. Retrieved from < https://www.uniprot.org/uniprot/AOA060M6U8 > on Feb. 8, 2021.
  • Attie et al., “Draft Genome Sequence of Bacillus alcalophilus AV1934, a Classic Alkaliphile Isolated from Human Feces in 1934”, Genome Announcements, Nov./Dec. 2014, vol. 2 Issue 6 e01175-14.
  • UniProt E0XH65—Bacillus lehensis G1 protease/subtilase, deposited Sep. 2014. Retrieved from < https://www.uniprot.org/uniprot/EOXH65 > on Feb. 8, 2021.
  • Search report issued for corresponding EP application No. 18209175.1 dated Jan. 10, 2019, 7 pages, (for information purpose only).
  • Altschul et al., “Gapped BLAST and PSI-BLAST: a new generation of protein database search programs”, Nucleic Acids Res., 1997, pp. 3389-3402, vol. 25, No. 17.
  • Bender et al., “The Determination of the Concentration of Hydrolytic Enzyme Solutions . . . ” J. Am. Chem. Soc. 88, 24, 1966, pp. 5890-5913, Dec. 20, 1966.
  • Search report issued for EP application No. 18209177.7 dated May 9, 2019, 7 pages, (for information purpose only).
Patent History
Patent number: 11359189
Type: Grant
Filed: Nov 28, 2019
Date of Patent: Jun 14, 2022
Patent Publication Number: 20200172888
Assignee: HENKEL AG & CO. KGAA (Duesseldorf)
Inventors: Christian Degering (Erkrath), Nina Mussmann (Willich), Inken Prueser (Duesseldorf), Susanne Wieland (Dormagen/Zons)
Primary Examiner: Suzanne M Noakes
Application Number: 16/699,017
Classifications
Current U.S. Class: Non/e
International Classification: C12N 9/50 (20060101); C11D 3/386 (20060101);